1. Field of the Invention
This invention relates generally to a card guide frame to support one or more substrates, and more specifically relates to an air-flow balancing card guide frame to control air-flow and support one or more printed circuit board assemblies of IC components.
2. Description of the Prior Art
In many data processing systems (e.g., computer systems, programmable electronic systems, telecommunication switching systems, control systems, and so forth) very large pin count electrical components (e.g., application specific integrated circuits and processor chips) are assembled on substrates (e.g., printed circuit boards, other flexible substrates, multi-chip modules, and equivalents). These substrates are typically supported by metal card guides, which allow the substrates to be inserted or extracted from the data processing system. Card guides typically supply physical support and rigidity to the substrates, and help maintain the proper electrical connections between the substrates.
However, conventional card guides typically block the air-flow intended to dissipate the heat generated by the operation of the substrates, particularly the heat generated by the integrated circuits assembled on the substrates. Without a proper distribution of air-flow, the heat generation ultimately raises the temperature of the substrates, and causes either permanent or an intermittent failures in the operation of the data processing system. Therefore, the air-flow must be carefully balanced and distributed inside the data processing system to provide sufficient air-flow to each substrate. The air-flow is typically controlled and distributed by the insertion of separately fabricated metal plates with holes to direct and control the air-flow to each substrate.
FIG. 1 illustrates a conventional card guide frame 102 for supporting substrates, such as printed circuit boards (PCB). The illustrated conventional card guide frame 102 can support three substrates (not shown), using card guides 104, 108 and 112, which contain card sockets 106, 110, and 114, respectively. Here, the air-flow to each substrate can be optionally controlled by the labor-intensive attachment of individual air-flow control plates (not shown) between the card guides 104, 108, and 112.
Conventional card guides are typically fabricated from a thick, heavy metal plate, or they are fabricated from an expensive thermo-set composite material (e.g., a graphite fiber epoxy composite). Frequently, such card guides are constrained in thickness and dimensions by the increasing packing densities of nearby substrates. Thick and heavy card guides may touch and damage adjacent components on adjacent substrates, and can be especially detrimental to system reliability when the system is subject to shock and vibration. However, thin and light card guides may distort and fail to adequately support the substrate. Without an improved card guide frame to provide a necessary amount of air-flow balancing to each substrate, considerable labor and expense are required to control the air-flow to prevent overheating and subsequent substrate failures.
It would be desirable to provide an improved card guide frame that can distribute the necessary amount of air-flow to each substrate, and also provide the necessary amount of mechanical support to each substrate.
The present invention provides an improved card guide frame that can distribute the necessary amount of air-flow to each substrate, and also provide the necessary amount of mechanical support to each substrate.
A first aspect of the invention is directed to a method to assemble an air-flow balancing card guide and one or more substrates. The method includes perforating a material with a plurality of holes having pre-selected shapes and pre-selected hole Spacings; shaping the material to form one or more air-flow control panels and one or more card guides; and attaching one or more substrates to the one or more card guides, wherein the one or more air-flow control panels will use the plurality of holes to control air-flow to the one or more substrates.
A second aspect of the invention is directed to a method to design an air-flow balancing card guide frame. The method includes selecting a set of physical dimensions of the air-flow balancing card guide frame; modeling the air-flow balancing card guide frame after insertion of one or more substrates; estimating a more precise set of physical dimensions for the air-flow balancing card guide frame after modeling the air-flow balancing card guide frame with one or more substrates; and shaping the airflow flow balancing card guide frame according to said set of physical dimensions.
A third aspect of the invention is directed to an assembled air-flow balancing card guide frame and one or more substrates. The assembled air-flow balancing card guide frame includes one or more card guides and one or more air-flow control panels; and one or more substrates attached to the one or more card guides, wherein the one or more substrates receive a directional air-flow controlled by the one or more air-flow control panels.
These and other objects and advantages of the invention will become apparent to those skilled in the art from the following detailed description of the invention and the accompanying drawings.